1. Field of the Invention:
The present invention relates to a phonograph for a record disk having a plurality of sound grooves, and in particular, to a simplified phonograph comprising selection rods corresponding in number to the number of sound grooves formed in a recording surface of a record disk unit, and a stylus pressure release actuating wheel normally urged in a predetermined direction of rotation for releasing the stylus pressure of a pickup when rotated in the opposite direction to the urged direction, by one of the selecting rods.
2. Description of the Prior Art:
A simplified phonograph capable of selectively reproducing a record disk having a plurality of sound grooves has been developed and known in the art. See, for example, U.S. Pat. No. 3,712,629 (corresponding to Great Britain Pat. No. 1336749, and Japanese Patent Publication No. 51-19763).
In a simplified phonograph, when one of the selection rods is depressed, the selection rod is pressed against a slant surface of the stylus pressure release actuating wheel to rotate same. As the stylus pressure release actuating wheel rotates, a stylus pressure release member, carried on the stylus pressure release actuating wheel, is moved together with the latter, and raises a speaker unit to return the pickup to a reproduction starting point on the recording surface of the record disk. At the same time, the selection rod engages a stopper pin, provided as an index portion no the record disk unit, and tentatively stops the rotation of the record disk unit, to thereby place a specified sound groove at a position at which the pickup, which has returned to the reproduction starting point, can engage. When the pressing pressure of the selection rod is released, the stylus pressure release member moves backwardly, together with the stylus pressure release actuating wheel, to release the support of the speaker unit. Thus, the stylus pressure of the pickup is applied.
In such a structure, if the selection rod is not sufficiently pressed so that the stopper pin engages the depressed selection rod, the stylus pressure will be applied while the pickup is still on its way back to the reproduction starting point. Thus, the selection of an intended sound groove will fail. The timing of the engagement of the stopper pin with the selection rod differs depending on the position of the stopper pin and the position of the selection rod, and this the operator cannot predict. As a result, the drawback is that, in the case of the simplified phonograph, the reliability of the selection and the speed of operation are lacking.
In order to solve such a drawback, a device has been provided as taught in U.S. Pat. No. 4,482,990 (corresponding to Japanese Patent Laid-Open Publication No. 60-5070l).
However, this device also involves a disadvantage in that the stylus release mechanism and the index mechanism are complicated, and it is difficult to simplify the device.
Furthermore, another device has been provided to improve the reliability of selection and the speedy operation as taught in U.S. Pat. No. 4,541,085 (corresponding to Japanese Patent Laid-Open Publication No. 60-76001). However, this device is disadvantageous in simplifying the device since the stylus pressure release mechanism and the index mechanism are complicated.